Add Merge Sort Linked List algorithm#11672

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
Hardvan wants to merge 2 commits into from
Closed

Add Merge Sort Linked List algorithm #11672

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
121bfda
Add Merge Sort Linked List algorithm
Hardvan Oct 2, 2024
7ee4af8
updating DIRECTORY.md
Hardvan Oct 2, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
1 change: 1 addition & 0 deletions DIRECTORY.md
View file
Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -261,6 +261,7 @@
* [From Sequence](data_structures/linked_list/from_sequence.py)
* [Has Loop](data_structures/linked_list/has_loop.py)
* [Is Palindrome](data_structures/linked_list/is_palindrome.py)
* [Merge Sort Linked List](data_structures/linked_list/merge_sort_linked_list.py)
* [Merge Two Lists](data_structures/linked_list/merge_two_lists.py)
* [Middle Element Of Linked List](data_structures/linked_list/middle_element_of_linked_list.py)
* [Print Reverse](data_structures/linked_list/print_reverse.py)
Expand Down
168 changes: 168 additions & 0 deletions data_structures/linked_list/merge_sort_linked_list.py
View file
Open in desktop
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,168 @@
class Node:
"""
A class representing a node in a linked list.

Attributes:
data (int): The data stored in the node.
next (Node | None): A reference to the next node in the linked list.

>>> head = Node(4)
>>> head.next = Node(2)
>>> head.next.next = Node(1)
>>> head.next.next.next = Node(3)
>>> sorted_head = merge_sort_linked_list(head)
>>> print_linked_list(sorted_head)
1 2 3 4
"""

def __init__(self, data: int):
self.data = data
self.next: Node | None = None


def get_middle(head: Node) -> Node:
"""
Find the middle node of the linked list using the slow and fast pointer technique.

Parameters:
head: The head node of the linked list.

Returns:
The middle node of the linked list.

Example:
>>> head = Node(1)
>>> head.next = Node(2)
>>> head.next.next = Node(3)
>>> get_middle(head).data
2
"""

if head is None:
return head

slow = head # one node at a time
fast = head # two nodes at a time
while fast.next and fast.next.next:
slow = slow.next
fast = fast.next.next
return slow


def merge(left: Node | None, right: Node | None) -> Node | None:
"""
Merge two sorted linked lists into one sorted linked list.

Parameters:
left: The head of the first sorted linked list.
right: The head of the second sorted linked list.

Returns:
The head of the merged sorted linked list.

Example:
>>> left = Node(1)
>>> left.next = Node(3)
>>> right = Node(2)
>>> right.next = Node(4)
>>> merged = merge(left, right)
>>> print_linked_list(merged)
1 2 3 4
"""

if left is None:
return right
if right is None:
return left

if left.data <= right.data:
result = left
result.next = merge(left.next, right)
else:
result = right
result.next = merge(left, right.next)

return result


def print_linked_list(head: Node | None) -> None:
"""
Print the linked list in a single line.

Parameters:
head: The head node of the linked list.

Example:
>>> head = Node(1)
>>> head.next = Node(2)
>>> head.next.next = Node(3)
>>> print_linked_list(head)
1 2 3
"""

current = head
first = True # To avoid printing space before the first element
while current:
if not first:
print(" ", end="")
print(current.data, end="")
first = False
current = current.next
print()


def merge_sort_linked_list(head: Node | None) -> Node | None:
"""
Sort a linked list using the Merge Sort algorithm.

Parameters:
head: The head node of the linked list to be sorted.

Returns:
The head node of the sorted linked list.

Example:
>>> head = Node(4)
>>> head.next = Node(2)
>>> head.next.next = Node(1)
>>> head.next.next.next = Node(3)
>>> sorted_head = merge_sort_linked_list(head)
>>> print_linked_list(sorted_head)
1 2 3 4

>>> head = Node(1)
>>> head.next = Node(2)
>>> head.next.next = Node(3)
>>> head.next.next.next = Node(4)
>>> sorted_head = merge_sort_linked_list(head)
>>> print_linked_list(sorted_head)
1 2 3 4

>>> head = Node(10)
>>> head.next = Node(3)
>>> head.next.next = Node(5)
>>> head.next.next.next = Node(1)
>>> sorted_head = merge_sort_linked_list(head)
>>> print_linked_list(sorted_head)
1 3 5 10
"""

# Base Case: 0 or 1 node
if head is None or head.next is None:
return head

# Split the linked list into two halves
middle = get_middle(head)
next_to_middle = middle.next
middle.next = None # Split the list into two parts

left = merge_sort_linked_list(head) # Sort the left half
right = merge_sort_linked_list(next_to_middle) # Sort the right half
sorted_list = merge(left, right) # Merge the sorted halves
return sorted_list


if __name__ == "__main__":
import doctest

doctest.testmod()
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
 blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

Skip to content
Add Merge Sort Linked List algorithm#11672

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

 Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and
privacy statement. We’ll occasionally send you account related emails.

Already on GitHub?
Sign in
to your account

 Closed

Hardvan
wants to merge
2
commits into

from

 Closed


Add Merge Sort Linked List algorithm
#11672
Show file tree
Hide file tree
 Changes from all commits
Commits

Show all changes


2 commits


Select commit
Hold shift + click to select a range
121bfda

Add Merge Sort Linked List algorithm


Hardvan Oct 2, 2024
7ee4af8

updating DIRECTORY.md


Hardvan Oct 2, 2024

File filter

Filter by extension
Filter by extension
Conversations

Failed to load comments. 
Loading
Jump to

Jump to file


Failed to load files. 
Loading
 Diff view

 Diff view


1 change: 1 addition & 0 deletions
DIRECTORY.md

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -261,6 +261,7 @@
 * [From Sequence](data_structures/linked_list/from_sequence.py)
 * [Has Loop](data_structures/linked_list/has_loop.py)
 * [Is Palindrome](data_structures/linked_list/is_palindrome.py)
 * [Merge Sort Linked List](data_structures/linked_list/merge_sort_linked_list.py)
 * [Merge Two Lists](data_structures/linked_list/merge_two_lists.py)
 * [Middle Element Of Linked List](data_structures/linked_list/middle_element_of_linked_list.py)
 * [Print Reverse](data_structures/linked_list/print_reverse.py)
Expand Down

168 changes: 168 additions & 0 deletions
data_structures/linked_list/merge_sort_linked_list.py

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,168 @@
class Node:
 """
 A class representing a node in a linked list.

 Attributes:
 data (int): The data stored in the node.
 next (Node | None): A reference to the next node in the linked list.

 >>> head = Node(4)
 >>> head.next = Node(2)
 >>> head.next.next = Node(1)
 >>> head.next.next.next = Node(3)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 2 3 4
 """

 def __init__(self, data: int):
 self.data = data
 self.next: Node | None = None


def get_middle(head: Node) -> Node:
 """
 Find the middle node of the linked list using the slow and fast pointer technique.

 Parameters:
 head: The head node of the linked list.

 Returns:
 The middle node of the linked list.

 Example:
 >>> head = Node(1)
 >>> head.next = Node(2)
 >>> head.next.next = Node(3)
 >>> get_middle(head).data
 2
 """

 if head is None:
 return head

 slow = head # one node at a time
 fast = head # two nodes at a time
 while fast.next and fast.next.next:
 slow = slow.next
 fast = fast.next.next
 return slow


def merge(left: Node | None, right: Node | None) -> Node | None:
 """
 Merge two sorted linked lists into one sorted linked list.

 Parameters:
 left: The head of the first sorted linked list.
 right: The head of the second sorted linked list.

 Returns:
 The head of the merged sorted linked list.

 Example:
 >>> left = Node(1)
 >>> left.next = Node(3)
 >>> right = Node(2)
 >>> right.next = Node(4)
 >>> merged = merge(left, right)
 >>> print_linked_list(merged)
 1 2 3 4
 """

 if left is None:
 return right
 if right is None:
 return left

 if left.data <= right.data:
 result = left
 result.next = merge(left.next, right)
 else:
 result = right
 result.next = merge(left, right.next)

 return result


def print_linked_list(head: Node | None) -> None:
 """
 Print the linked list in a single line.

 Parameters:
 head: The head node of the linked list.

 Example:
 >>> head = Node(1)
 >>> head.next = Node(2)
 >>> head.next.next = Node(3)
 >>> print_linked_list(head)
 1 2 3
 """

 current = head
 first = True # To avoid printing space before the first element
 while current:
 if not first:
 print(" ", end="")
 print(current.data, end="")
 first = False
 current = current.next
 print()


def merge_sort_linked_list(head: Node | None) -> Node | None:
 """
 Sort a linked list using the Merge Sort algorithm.

 Parameters:
 head: The head node of the linked list to be sorted.

 Returns:
 The head node of the sorted linked list.

 Example:
 >>> head = Node(4)
 >>> head.next = Node(2)
 >>> head.next.next = Node(1)
 >>> head.next.next.next = Node(3)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 2 3 4

 >>> head = Node(1)
 >>> head.next = Node(2)
 >>> head.next.next = Node(3)
 >>> head.next.next.next = Node(4)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 2 3 4

 >>> head = Node(10)
 >>> head.next = Node(3)
 >>> head.next.next = Node(5)
 >>> head.next.next.next = Node(1)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 3 5 10
 """

 # Base Case: 0 or 1 node
 if head is None or head.next is None:
 return head

 # Split the linked list into two halves
 middle = get_middle(head)
 next_to_middle = middle.next
 middle.next = None # Split the list into two parts

 left = merge_sort_linked_list(head) # Sort the left half
 right = merge_sort_linked_list(next_to_middle) # Sort the right half
 sorted_list = merge(left, right) # Merge the sorted halves
 return sorted_list


if __name__ == "__main__":
 import doctest

 doctest.testmod()

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
Add Merge Sort Linked List algorithm#11672

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

 Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and
privacy statement. We’ll occasionally send you account related emails.

Already on GitHub?
Sign in
to your account

 Closed

Hardvan
wants to merge
2
commits into

from

 Closed


Add Merge Sort Linked List algorithm
#11672
Show file tree
Hide file tree
 Changes from all commits
Commits

Show all changes


2 commits


Select commit
Hold shift + click to select a range
121bfda

Add Merge Sort Linked List algorithm


Hardvan Oct 2, 2024
7ee4af8

updating DIRECTORY.md


Hardvan Oct 2, 2024

File filter

Filter by extension
Filter by extension
Conversations

Failed to load comments. 
Loading
Jump to

Jump to file


Failed to load files. 
Loading
 Diff view

 Diff view


1 change: 1 addition & 0 deletions
DIRECTORY.md

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -261,6 +261,7 @@
 * [From Sequence](data_structures/linked_list/from_sequence.py)
 * [Has Loop](data_structures/linked_list/has_loop.py)
 * [Is Palindrome](data_structures/linked_list/is_palindrome.py)
 * [Merge Sort Linked List](data_structures/linked_list/merge_sort_linked_list.py)
 * [Merge Two Lists](data_structures/linked_list/merge_two_lists.py)
 * [Middle Element Of Linked List](data_structures/linked_list/middle_element_of_linked_list.py)
 * [Print Reverse](data_structures/linked_list/print_reverse.py)
Expand Down

168 changes: 168 additions & 0 deletions
data_structures/linked_list/merge_sort_linked_list.py

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,168 @@
class Node:
 """
 A class representing a node in a linked list.

 Attributes:
 data (int): The data stored in the node.
 next (Node | None): A reference to the next node in the linked list.

 >>> head = Node(4)
 >>> head.next = Node(2)
 >>> head.next.next = Node(1)
 >>> head.next.next.next = Node(3)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 2 3 4
 """

 def __init__(self, data: int):
 self.data = data
 self.next: Node | None = None


def get_middle(head: Node) -> Node:
 """
 Find the middle node of the linked list using the slow and fast pointer technique.

 Parameters:
 head: The head node of the linked list.

 Returns:
 The middle node of the linked list.

 Example:
 >>> head = Node(1)
 >>> head.next = Node(2)
 >>> head.next.next = Node(3)
 >>> get_middle(head).data
 2
 """

 if head is None:
 return head

 slow = head # one node at a time
 fast = head # two nodes at a time
 while fast.next and fast.next.next:
 slow = slow.next
 fast = fast.next.next
 return slow


def merge(left: Node | None, right: Node | None) -> Node | None:
 """
 Merge two sorted linked lists into one sorted linked list.

 Parameters:
 left: The head of the first sorted linked list.
 right: The head of the second sorted linked list.

 Returns:
 The head of the merged sorted linked list.

 Example:
 >>> left = Node(1)
 >>> left.next = Node(3)
 >>> right = Node(2)
 >>> right.next = Node(4)
 >>> merged = merge(left, right)
 >>> print_linked_list(merged)
 1 2 3 4
 """

 if left is None:
 return right
 if right is None:
 return left

 if left.data <= right.data:
 result = left
 result.next = merge(left.next, right)
 else:
 result = right
 result.next = merge(left, right.next)

 return result


def print_linked_list(head: Node | None) -> None:
 """
 Print the linked list in a single line.

 Parameters:
 head: The head node of the linked list.

 Example:
 >>> head = Node(1)
 >>> head.next = Node(2)
 >>> head.next.next = Node(3)
 >>> print_linked_list(head)
 1 2 3
 """

 current = head
 first = True # To avoid printing space before the first element
 while current:
 if not first:
 print(" ", end="")
 print(current.data, end="")
 first = False
 current = current.next
 print()


def merge_sort_linked_list(head: Node | None) -> Node | None:
 """
 Sort a linked list using the Merge Sort algorithm.

 Parameters:
 head: The head node of the linked list to be sorted.

 Returns:
 The head node of the sorted linked list.

 Example:
 >>> head = Node(4)
 >>> head.next = Node(2)
 >>> head.next.next = Node(1)
 >>> head.next.next.next = Node(3)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 2 3 4

 >>> head = Node(1)
 >>> head.next = Node(2)
 >>> head.next.next = Node(3)
 >>> head.next.next.next = Node(4)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 2 3 4

 >>> head = Node(10)
 >>> head.next = Node(3)
 >>> head.next.next = Node(5)
 >>> head.next.next.next = Node(1)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 3 5 10
 """

 # Base Case: 0 or 1 node
 if head is None or head.next is None:
 return head

 # Split the linked list into two halves
 middle = get_middle(head)
 next_to_middle = middle.next
 middle.next = None # Split the list into two parts

 left = merge_sort_linked_list(head) # Sort the left half
 right = merge_sort_linked_list(next_to_middle) # Sort the right half
 sorted_list = merge(left, right) # Merge the sorted halves
 return sorted_list


if __name__ == "__main__":
 import doctest

 doctest.testmod()

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
Add Merge Sort Linked List algorithm#11672

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

 Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and
privacy statement. We’ll occasionally send you account related emails.

Already on GitHub?
Sign in
to your account

 Closed

Hardvan
wants to merge
2
commits into

from

 Closed


Add Merge Sort Linked List algorithm
#11672
Show file tree
Hide file tree
 Changes from all commits
Commits

Show all changes


2 commits


Select commit
Hold shift + click to select a range
121bfda

Add Merge Sort Linked List algorithm


Hardvan Oct 2, 2024
7ee4af8

updating DIRECTORY.md


Hardvan Oct 2, 2024

File filter

Filter by extension
Filter by extension
Conversations

Failed to load comments. 
Loading
Jump to

Jump to file


Failed to load files. 
Loading
 Diff view

 Diff view


1 change: 1 addition & 0 deletions
DIRECTORY.md

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -261,6 +261,7 @@
 * [From Sequence](data_structures/linked_list/from_sequence.py)
 * [Has Loop](data_structures/linked_list/has_loop.py)
 * [Is Palindrome](data_structures/linked_list/is_palindrome.py)
 * [Merge Sort Linked List](data_structures/linked_list/merge_sort_linked_list.py)
 * [Merge Two Lists](data_structures/linked_list/merge_two_lists.py)
 * [Middle Element Of Linked List](data_structures/linked_list/middle_element_of_linked_list.py)
 * [Print Reverse](data_structures/linked_list/print_reverse.py)
Expand Down

168 changes: 168 additions & 0 deletions
data_structures/linked_list/merge_sort_linked_list.py

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,168 @@
class Node:
 """
 A class representing a node in a linked list.

 Attributes:
 data (int): The data stored in the node.
 next (Node | None): A reference to the next node in the linked list.

 >>> head = Node(4)
 >>> head.next = Node(2)
 >>> head.next.next = Node(1)
 >>> head.next.next.next = Node(3)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 2 3 4
 """

 def __init__(self, data: int):
 self.data = data
 self.next: Node | None = None


def get_middle(head: Node) -> Node:
 """
 Find the middle node of the linked list using the slow and fast pointer technique.

 Parameters:
 head: The head node of the linked list.

 Returns:
 The middle node of the linked list.

 Example:
 >>> head = Node(1)
 >>> head.next = Node(2)
 >>> head.next.next = Node(3)
 >>> get_middle(head).data
 2
 """

 if head is None:
 return head

 slow = head # one node at a time
 fast = head # two nodes at a time
 while fast.next and fast.next.next:
 slow = slow.next
 fast = fast.next.next
 return slow


def merge(left: Node | None, right: Node | None) -> Node | None:
 """
 Merge two sorted linked lists into one sorted linked list.

 Parameters:
 left: The head of the first sorted linked list.
 right: The head of the second sorted linked list.

 Returns:
 The head of the merged sorted linked list.

 Example:
 >>> left = Node(1)
 >>> left.next = Node(3)
 >>> right = Node(2)
 >>> right.next = Node(4)
 >>> merged = merge(left, right)
 >>> print_linked_list(merged)
 1 2 3 4
 """

 if left is None:
 return right
 if right is None:
 return left

 if left.data <= right.data:
 result = left
 result.next = merge(left.next, right)
 else:
 result = right
 result.next = merge(left, right.next)

 return result


def print_linked_list(head: Node | None) -> None:
 """
 Print the linked list in a single line.

 Parameters:
 head: The head node of the linked list.

 Example:
 >>> head = Node(1)
 >>> head.next = Node(2)
 >>> head.next.next = Node(3)
 >>> print_linked_list(head)
 1 2 3
 """

 current = head
 first = True # To avoid printing space before the first element
 while current:
 if not first:
 print(" ", end="")
 print(current.data, end="")
 first = False
 current = current.next
 print()


def merge_sort_linked_list(head: Node | None) -> Node | None:
 """
 Sort a linked list using the Merge Sort algorithm.

 Parameters:
 head: The head node of the linked list to be sorted.

 Returns:
 The head node of the sorted linked list.

 Example:
 >>> head = Node(4)
 >>> head.next = Node(2)
 >>> head.next.next = Node(1)
 >>> head.next.next.next = Node(3)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 2 3 4

 >>> head = Node(1)
 >>> head.next = Node(2)
 >>> head.next.next = Node(3)
 >>> head.next.next.next = Node(4)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 2 3 4

 >>> head = Node(10)
 >>> head.next = Node(3)
 >>> head.next.next = Node(5)
 >>> head.next.next.next = Node(1)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 3 5 10
 """

 # Base Case: 0 or 1 node
 if head is None or head.next is None:
 return head

 # Split the linked list into two halves
 middle = get_middle(head)
 next_to_middle = middle.next
 middle.next = None # Split the list into two parts

 left = merge_sort_linked_list(head) # Sort the left half
 right = merge_sort_linked_list(next_to_middle) # Sort the right half
 sorted_list = merge(left, right) # Merge the sorted halves
 return sorted_list


if __name__ == "__main__":
 import doctest

 doctest.testmod()

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

Skip to content
Add Merge Sort Linked List algorithm#11672

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

 Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and
privacy statement. We’ll occasionally send you account related emails.

Already on GitHub?
Sign in
to your account

 Closed

Hardvan
wants to merge
2
commits into

from

 Closed


Add Merge Sort Linked List algorithm
#11672
Show file tree
Hide file tree
 Changes from all commits
Commits

Show all changes


2 commits


Select commit
Hold shift + click to select a range
121bfda

Add Merge Sort Linked List algorithm


Hardvan Oct 2, 2024
7ee4af8

updating DIRECTORY.md


Hardvan Oct 2, 2024

File filter

Filter by extension
Filter by extension
Conversations

Failed to load comments. 
Loading
Jump to

Jump to file


Failed to load files. 
Loading
 Diff view

 Diff view


1 change: 1 addition & 0 deletions
DIRECTORY.md

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -261,6 +261,7 @@
 * [From Sequence](data_structures/linked_list/from_sequence.py)
 * [Has Loop](data_structures/linked_list/has_loop.py)
 * [Is Palindrome](data_structures/linked_list/is_palindrome.py)
 * [Merge Sort Linked List](data_structures/linked_list/merge_sort_linked_list.py)
 * [Merge Two Lists](data_structures/linked_list/merge_two_lists.py)
 * [Middle Element Of Linked List](data_structures/linked_list/middle_element_of_linked_list.py)
 * [Print Reverse](data_structures/linked_list/print_reverse.py)
Expand Down

168 changes: 168 additions & 0 deletions
data_structures/linked_list/merge_sort_linked_list.py

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,168 @@
class Node:
 """
 A class representing a node in a linked list.

 Attributes:
 data (int): The data stored in the node.
 next (Node | None): A reference to the next node in the linked list.

 >>> head = Node(4)
 >>> head.next = Node(2)
 >>> head.next.next = Node(1)
 >>> head.next.next.next = Node(3)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 2 3 4
 """

 def __init__(self, data: int):
 self.data = data
 self.next: Node | None = None


def get_middle(head: Node) -> Node:
 """
 Find the middle node of the linked list using the slow and fast pointer technique.

 Parameters:
 head: The head node of the linked list.

 Returns:
 The middle node of the linked list.

 Example:
 >>> head = Node(1)
 >>> head.next = Node(2)
 >>> head.next.next = Node(3)
 >>> get_middle(head).data
 2
 """

 if head is None:
 return head

 slow = head # one node at a time
 fast = head # two nodes at a time
 while fast.next and fast.next.next:
 slow = slow.next
 fast = fast.next.next
 return slow


def merge(left: Node | None, right: Node | None) -> Node | None:
 """
 Merge two sorted linked lists into one sorted linked list.

 Parameters:
 left: The head of the first sorted linked list.
 right: The head of the second sorted linked list.

 Returns:
 The head of the merged sorted linked list.

 Example:
 >>> left = Node(1)
 >>> left.next = Node(3)
 >>> right = Node(2)
 >>> right.next = Node(4)
 >>> merged = merge(left, right)
 >>> print_linked_list(merged)
 1 2 3 4
 """

 if left is None:
 return right
 if right is None:
 return left

 if left.data <= right.data:
 result = left
 result.next = merge(left.next, right)
 else:
 result = right
 result.next = merge(left, right.next)

 return result


def print_linked_list(head: Node | None) -> None:
 """
 Print the linked list in a single line.

 Parameters:
 head: The head node of the linked list.

 Example:
 >>> head = Node(1)
 >>> head.next = Node(2)
 >>> head.next.next = Node(3)
 >>> print_linked_list(head)
 1 2 3
 """

 current = head
 first = True # To avoid printing space before the first element
 while current:
 if not first:
 print(" ", end="")
 print(current.data, end="")
 first = False
 current = current.next
 print()


def merge_sort_linked_list(head: Node | None) -> Node | None:
 """
 Sort a linked list using the Merge Sort algorithm.

 Parameters:
 head: The head node of the linked list to be sorted.

 Returns:
 The head node of the sorted linked list.

 Example:
 >>> head = Node(4)
 >>> head.next = Node(2)
 >>> head.next.next = Node(1)
 >>> head.next.next.next = Node(3)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 2 3 4

 >>> head = Node(1)
 >>> head.next = Node(2)
 >>> head.next.next = Node(3)
 >>> head.next.next.next = Node(4)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 2 3 4

 >>> head = Node(10)
 >>> head.next = Node(3)
 >>> head.next.next = Node(5)
 >>> head.next.next.next = Node(1)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 3 5 10
 """

 # Base Case: 0 or 1 node
 if head is None or head.next is None:
 return head

 # Split the linked list into two halves
 middle = get_middle(head)
 next_to_middle = middle.next
 middle.next = None # Split the list into two parts

 left = merge_sort_linked_list(head) # Sort the left half
 right = merge_sort_linked_list(next_to_middle) # Sort the right half
 sorted_list = merge(left, right) # Merge the sorted halves
 return sorted_list


if __name__ == "__main__":
 import doctest

 doctest.testmod()

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
Add Merge Sort Linked List algorithm#11672

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

 Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and
privacy statement. We’ll occasionally send you account related emails.

Already on GitHub?
Sign in
to your account

 Closed

Hardvan
wants to merge
2
commits into

from

 Closed


Add Merge Sort Linked List algorithm
#11672
Show file tree
Hide file tree
 Changes from all commits
Commits

Show all changes


2 commits


Select commit
Hold shift + click to select a range
121bfda

Add Merge Sort Linked List algorithm


Hardvan Oct 2, 2024
7ee4af8

updating DIRECTORY.md


Hardvan Oct 2, 2024

File filter

Filter by extension
Filter by extension
Conversations

Failed to load comments. 
Loading
Jump to

Jump to file


Failed to load files. 
Loading
 Diff view

 Diff view


1 change: 1 addition & 0 deletions
DIRECTORY.md

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -261,6 +261,7 @@
 * [From Sequence](data_structures/linked_list/from_sequence.py)
 * [Has Loop](data_structures/linked_list/has_loop.py)
 * [Is Palindrome](data_structures/linked_list/is_palindrome.py)
 * [Merge Sort Linked List](data_structures/linked_list/merge_sort_linked_list.py)
 * [Merge Two Lists](data_structures/linked_list/merge_two_lists.py)
 * [Middle Element Of Linked List](data_structures/linked_list/middle_element_of_linked_list.py)
 * [Print Reverse](data_structures/linked_list/print_reverse.py)
Expand Down

168 changes: 168 additions & 0 deletions
data_structures/linked_list/merge_sort_linked_list.py

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,168 @@
class Node:
 """
 A class representing a node in a linked list.

 Attributes:
 data (int): The data stored in the node.
 next (Node | None): A reference to the next node in the linked list.

 >>> head = Node(4)
 >>> head.next = Node(2)
 >>> head.next.next = Node(1)
 >>> head.next.next.next = Node(3)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 2 3 4
 """

 def __init__(self, data: int):
 self.data = data
 self.next: Node | None = None


def get_middle(head: Node) -> Node:
 """
 Find the middle node of the linked list using the slow and fast pointer technique.

 Parameters:
 head: The head node of the linked list.

 Returns:
 The middle node of the linked list.

 Example:
 >>> head = Node(1)
 >>> head.next = Node(2)
 >>> head.next.next = Node(3)
 >>> get_middle(head).data
 2
 """

 if head is None:
 return head

 slow = head # one node at a time
 fast = head # two nodes at a time
 while fast.next and fast.next.next:
 slow = slow.next
 fast = fast.next.next
 return slow


def merge(left: Node | None, right: Node | None) -> Node | None:
 """
 Merge two sorted linked lists into one sorted linked list.

 Parameters:
 left: The head of the first sorted linked list.
 right: The head of the second sorted linked list.

 Returns:
 The head of the merged sorted linked list.

 Example:
 >>> left = Node(1)
 >>> left.next = Node(3)
 >>> right = Node(2)
 >>> right.next = Node(4)
 >>> merged = merge(left, right)
 >>> print_linked_list(merged)
 1 2 3 4
 """

 if left is None:
 return right
 if right is None:
 return left

 if left.data <= right.data:
 result = left
 result.next = merge(left.next, right)
 else:
 result = right
 result.next = merge(left, right.next)

 return result


def print_linked_list(head: Node | None) -> None:
 """
 Print the linked list in a single line.

 Parameters:
 head: The head node of the linked list.

 Example:
 >>> head = Node(1)
 >>> head.next = Node(2)
 >>> head.next.next = Node(3)
 >>> print_linked_list(head)
 1 2 3
 """

 current = head
 first = True # To avoid printing space before the first element
 while current:
 if not first:
 print(" ", end="")
 print(current.data, end="")
 first = False
 current = current.next
 print()


def merge_sort_linked_list(head: Node | None) -> Node | None:
 """
 Sort a linked list using the Merge Sort algorithm.

 Parameters:
 head: The head node of the linked list to be sorted.

 Returns:
 The head node of the sorted linked list.

 Example:
 >>> head = Node(4)
 >>> head.next = Node(2)
 >>> head.next.next = Node(1)
 >>> head.next.next.next = Node(3)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 2 3 4

 >>> head = Node(1)
 >>> head.next = Node(2)
 >>> head.next.next = Node(3)
 >>> head.next.next.next = Node(4)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 2 3 4

 >>> head = Node(10)
 >>> head.next = Node(3)
 >>> head.next.next = Node(5)
 >>> head.next.next.next = Node(1)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 3 5 10
 """

 # Base Case: 0 or 1 node
 if head is None or head.next is None:
 return head

 # Split the linked list into two halves
 middle = get_middle(head)
 next_to_middle = middle.next
 middle.next = None # Split the list into two parts

 left = merge_sort_linked_list(head) # Sort the left half
 right = merge_sort_linked_list(next_to_middle) # Sort the right half
 sorted_list = merge(left, right) # Merge the sorted halves
 return sorted_list


if __name__ == "__main__":
 import doctest

 doctest.testmod()

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
Add Merge Sort Linked List algorithm#11672

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

 Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and
privacy statement. We’ll occasionally send you account related emails.

Already on GitHub?
Sign in
to your account

 Closed

Hardvan
wants to merge
2
commits into

from

 Closed


Add Merge Sort Linked List algorithm
#11672
Show file tree
Hide file tree
 Changes from all commits
Commits

Show all changes


2 commits


Select commit
Hold shift + click to select a range
121bfda

Add Merge Sort Linked List algorithm


Hardvan Oct 2, 2024
7ee4af8

updating DIRECTORY.md


Hardvan Oct 2, 2024

File filter

Filter by extension
Filter by extension
Conversations

Failed to load comments. 
Loading
Jump to

Jump to file


Failed to load files. 
Loading
 Diff view

 Diff view


1 change: 1 addition & 0 deletions
DIRECTORY.md

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -261,6 +261,7 @@
 * [From Sequence](data_structures/linked_list/from_sequence.py)
 * [Has Loop](data_structures/linked_list/has_loop.py)
 * [Is Palindrome](data_structures/linked_list/is_palindrome.py)
 * [Merge Sort Linked List](data_structures/linked_list/merge_sort_linked_list.py)
 * [Merge Two Lists](data_structures/linked_list/merge_two_lists.py)
 * [Middle Element Of Linked List](data_structures/linked_list/middle_element_of_linked_list.py)
 * [Print Reverse](data_structures/linked_list/print_reverse.py)
Expand Down

168 changes: 168 additions & 0 deletions
data_structures/linked_list/merge_sort_linked_list.py

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,168 @@
class Node:
 """
 A class representing a node in a linked list.

 Attributes:
 data (int): The data stored in the node.
 next (Node | None): A reference to the next node in the linked list.

 >>> head = Node(4)
 >>> head.next = Node(2)
 >>> head.next.next = Node(1)
 >>> head.next.next.next = Node(3)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 2 3 4
 """

 def __init__(self, data: int):
 self.data = data
 self.next: Node | None = None


def get_middle(head: Node) -> Node:
 """
 Find the middle node of the linked list using the slow and fast pointer technique.

 Parameters:
 head: The head node of the linked list.

 Returns:
 The middle node of the linked list.

 Example:
 >>> head = Node(1)
 >>> head.next = Node(2)
 >>> head.next.next = Node(3)
 >>> get_middle(head).data
 2
 """

 if head is None:
 return head

 slow = head # one node at a time
 fast = head # two nodes at a time
 while fast.next and fast.next.next:
 slow = slow.next
 fast = fast.next.next
 return slow


def merge(left: Node | None, right: Node | None) -> Node | None:
 """
 Merge two sorted linked lists into one sorted linked list.

 Parameters:
 left: The head of the first sorted linked list.
 right: The head of the second sorted linked list.

 Returns:
 The head of the merged sorted linked list.

 Example:
 >>> left = Node(1)
 >>> left.next = Node(3)
 >>> right = Node(2)
 >>> right.next = Node(4)
 >>> merged = merge(left, right)
 >>> print_linked_list(merged)
 1 2 3 4
 """

 if left is None:
 return right
 if right is None:
 return left

 if left.data <= right.data:
 result = left
 result.next = merge(left.next, right)
 else:
 result = right
 result.next = merge(left, right.next)

 return result


def print_linked_list(head: Node | None) -> None:
 """
 Print the linked list in a single line.

 Parameters:
 head: The head node of the linked list.

 Example:
 >>> head = Node(1)
 >>> head.next = Node(2)
 >>> head.next.next = Node(3)
 >>> print_linked_list(head)
 1 2 3
 """

 current = head
 first = True # To avoid printing space before the first element
 while current:
 if not first:
 print(" ", end="")
 print(current.data, end="")
 first = False
 current = current.next
 print()


def merge_sort_linked_list(head: Node | None) -> Node | None:
 """
 Sort a linked list using the Merge Sort algorithm.

 Parameters:
 head: The head node of the linked list to be sorted.

 Returns:
 The head node of the sorted linked list.

 Example:
 >>> head = Node(4)
 >>> head.next = Node(2)
 >>> head.next.next = Node(1)
 >>> head.next.next.next = Node(3)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 2 3 4

 >>> head = Node(1)
 >>> head.next = Node(2)
 >>> head.next.next = Node(3)
 >>> head.next.next.next = Node(4)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 2 3 4

 >>> head = Node(10)
 >>> head.next = Node(3)
 >>> head.next.next = Node(5)
 >>> head.next.next.next = Node(1)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 3 5 10
 """

 # Base Case: 0 or 1 node
 if head is None or head.next is None:
 return head

 # Split the linked list into two halves
 middle = get_middle(head)
 next_to_middle = middle.next
 middle.next = None # Split the list into two parts

 left = merge_sort_linked_list(head) # Sort the left half
 right = merge_sort_linked_list(next_to_middle) # Sort the right half
 sorted_list = merge(left, right) # Merge the sorted halves
 return sorted_list


if __name__ == "__main__":
 import doctest

 doctest.testmod()

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

Skip to content
Add Merge Sort Linked List algorithm#11672

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

 Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and
privacy statement. We’ll occasionally send you account related emails.

Already on GitHub?
Sign in
to your account

 Closed

Hardvan
wants to merge
2
commits into

from

 Closed


Add Merge Sort Linked List algorithm
#11672
Show file tree
Hide file tree
 Changes from all commits
Commits

Show all changes


2 commits


Select commit
Hold shift + click to select a range
121bfda

Add Merge Sort Linked List algorithm


Hardvan Oct 2, 2024
7ee4af8

updating DIRECTORY.md


Hardvan Oct 2, 2024

File filter

Filter by extension
Filter by extension
Conversations

Failed to load comments. 
Loading
Jump to

Jump to file


Failed to load files. 
Loading
 Diff view

 Diff view


1 change: 1 addition & 0 deletions
DIRECTORY.md

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -261,6 +261,7 @@
 * [From Sequence](data_structures/linked_list/from_sequence.py)
 * [Has Loop](data_structures/linked_list/has_loop.py)
 * [Is Palindrome](data_structures/linked_list/is_palindrome.py)
 * [Merge Sort Linked List](data_structures/linked_list/merge_sort_linked_list.py)
 * [Merge Two Lists](data_structures/linked_list/merge_two_lists.py)
 * [Middle Element Of Linked List](data_structures/linked_list/middle_element_of_linked_list.py)
 * [Print Reverse](data_structures/linked_list/print_reverse.py)
Expand Down

168 changes: 168 additions & 0 deletions
data_structures/linked_list/merge_sort_linked_list.py

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,168 @@
class Node:
 """
 A class representing a node in a linked list.

 Attributes:
 data (int): The data stored in the node.
 next (Node | None): A reference to the next node in the linked list.

 >>> head = Node(4)
 >>> head.next = Node(2)
 >>> head.next.next = Node(1)
 >>> head.next.next.next = Node(3)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 2 3 4
 """

 def __init__(self, data: int):
 self.data = data
 self.next: Node | None = None


def get_middle(head: Node) -> Node:
 """
 Find the middle node of the linked list using the slow and fast pointer technique.

 Parameters:
 head: The head node of the linked list.

 Returns:
 The middle node of the linked list.

 Example:
 >>> head = Node(1)
 >>> head.next = Node(2)
 >>> head.next.next = Node(3)
 >>> get_middle(head).data
 2
 """

 if head is None:
 return head

 slow = head # one node at a time
 fast = head # two nodes at a time
 while fast.next and fast.next.next:
 slow = slow.next
 fast = fast.next.next
 return slow


def merge(left: Node | None, right: Node | None) -> Node | None:
 """
 Merge two sorted linked lists into one sorted linked list.

 Parameters:
 left: The head of the first sorted linked list.
 right: The head of the second sorted linked list.

 Returns:
 The head of the merged sorted linked list.

 Example:
 >>> left = Node(1)
 >>> left.next = Node(3)
 >>> right = Node(2)
 >>> right.next = Node(4)
 >>> merged = merge(left, right)
 >>> print_linked_list(merged)
 1 2 3 4
 """

 if left is None:
 return right
 if right is None:
 return left

 if left.data <= right.data:
 result = left
 result.next = merge(left.next, right)
 else:
 result = right
 result.next = merge(left, right.next)

 return result


def print_linked_list(head: Node | None) -> None:
 """
 Print the linked list in a single line.

 Parameters:
 head: The head node of the linked list.

 Example:
 >>> head = Node(1)
 >>> head.next = Node(2)
 >>> head.next.next = Node(3)
 >>> print_linked_list(head)
 1 2 3
 """

 current = head
 first = True # To avoid printing space before the first element
 while current:
 if not first:
 print(" ", end="")
 print(current.data, end="")
 first = False
 current = current.next
 print()


def merge_sort_linked_list(head: Node | None) -> Node | None:
 """
 Sort a linked list using the Merge Sort algorithm.

 Parameters:
 head: The head node of the linked list to be sorted.

 Returns:
 The head node of the sorted linked list.

 Example:
 >>> head = Node(4)
 >>> head.next = Node(2)
 >>> head.next.next = Node(1)
 >>> head.next.next.next = Node(3)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 2 3 4

 >>> head = Node(1)
 >>> head.next = Node(2)
 >>> head.next.next = Node(3)
 >>> head.next.next.next = Node(4)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 2 3 4

 >>> head = Node(10)
 >>> head.next = Node(3)
 >>> head.next.next = Node(5)
 >>> head.next.next.next = Node(1)
 >>> sorted_head = merge_sort_linked_list(head)
 >>> print_linked_list(sorted_head)
 1 3 5 10
 """

 # Base Case: 0 or 1 node
 if head is None or head.next is None:
 return head

 # Split the linked list into two halves
 middle = get_middle(head)
 next_to_middle = middle.next
 middle.next = None # Split the list into two parts

 left = merge_sort_linked_list(head) # Sort the left half
 right = merge_sort_linked_list(next_to_middle) # Sort the right half
 sorted_list = merge(left, right) # Merge the sorted halves
 return sorted_list


if __name__ == "__main__":
 import doctest

 doctest.testmod()